From d2e87b74ac4e37e6cb30f4aeab4ff0958358f524 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trondmy@gmail.com>
Date: Mon, 6 Jan 2020 15:25:08 -0500
Subject: [PATCH] NFS: Clean up generic file read tracepoints

Clean up the generic file read tracepoints so they do pass the
full structures as arguments. Also ensure we report the number
of bytes actually read.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
 fs/nfs/nfstrace.h | 56 ++++++++++++++++++++++++++++-------------------
 fs/nfs/read.c     |  5 ++---
 2 files changed, 35 insertions(+), 26 deletions(-)

diff --git a/fs/nfs/nfstrace.h b/fs/nfs/nfstrace.h
index 4d6eb17039437..0710b91f82d35 100644
--- a/fs/nfs/nfstrace.h
+++ b/fs/nfs/nfstrace.h
@@ -820,75 +820,85 @@ TRACE_EVENT(nfs_sillyrename_unlink,
 
 TRACE_EVENT(nfs_initiate_read,
 		TP_PROTO(
-			const struct inode *inode,
-			loff_t offset, unsigned long count
+			const struct nfs_pgio_header *hdr
 		),
 
-		TP_ARGS(inode, offset, count),
+		TP_ARGS(hdr),
 
 		TP_STRUCT__entry(
-			__field(loff_t, offset)
-			__field(unsigned long, count)
 			__field(dev_t, dev)
 			__field(u32, fhandle)
 			__field(u64, fileid)
+			__field(loff_t, offset)
+			__field(u32, count)
 		),
 
 		TP_fast_assign(
+			const struct inode *inode = hdr->inode;
 			const struct nfs_inode *nfsi = NFS_I(inode);
+			const struct nfs_fh *fh = hdr->args.fh ?
+						  hdr->args.fh : &nfsi->fh;
 
-			__entry->offset = offset;
-			__entry->count = count;
+			__entry->offset = hdr->args.offset;
+			__entry->count = hdr->args.count;
 			__entry->dev = inode->i_sb->s_dev;
 			__entry->fileid = nfsi->fileid;
-			__entry->fhandle = nfs_fhandle_hash(&nfsi->fh);
+			__entry->fhandle = nfs_fhandle_hash(fh);
 		),
 
 		TP_printk(
 			"fileid=%02x:%02x:%llu fhandle=0x%08x "
-			"offset=%lld count=%lu",
+			"offset=%lld count=%u",
 			MAJOR(__entry->dev), MINOR(__entry->dev),
 			(unsigned long long)__entry->fileid,
 			__entry->fhandle,
-			__entry->offset, __entry->count
+			(long long)__entry->offset, __entry->count
 		)
 );
 
 TRACE_EVENT(nfs_readpage_done,
 		TP_PROTO(
-			const struct inode *inode,
-			int status, loff_t offset, bool eof
+			const struct rpc_task *task,
+			const struct nfs_pgio_header *hdr
 		),
 
-		TP_ARGS(inode, status, offset, eof),
+		TP_ARGS(task, hdr),
 
 		TP_STRUCT__entry(
-			__field(int, status)
-			__field(loff_t, offset)
-			__field(bool, eof)
 			__field(dev_t, dev)
 			__field(u32, fhandle)
 			__field(u64, fileid)
+			__field(loff_t, offset)
+			__field(u32, arg_count)
+			__field(u32, res_count)
+			__field(bool, eof)
+			__field(int, status)
 		),
 
 		TP_fast_assign(
+			const struct inode *inode = hdr->inode;
 			const struct nfs_inode *nfsi = NFS_I(inode);
-
-			__entry->status = status;
-			__entry->offset = offset;
-			__entry->eof = eof;
+			const struct nfs_fh *fh = hdr->args.fh ?
+						  hdr->args.fh : &nfsi->fh;
+
+			__entry->status = task->tk_status;
+			__entry->offset = hdr->args.offset;
+			__entry->arg_count = hdr->args.count;
+			__entry->res_count = hdr->res.count;
+			__entry->eof = hdr->res.eof;
 			__entry->dev = inode->i_sb->s_dev;
 			__entry->fileid = nfsi->fileid;
-			__entry->fhandle = nfs_fhandle_hash(&nfsi->fh);
+			__entry->fhandle = nfs_fhandle_hash(fh);
 		),
 
 		TP_printk(
 			"fileid=%02x:%02x:%llu fhandle=0x%08x "
-			"offset=%lld status=%d%s",
+			"offset=%lld count=%u res=%u status=%d%s",
 			MAJOR(__entry->dev), MINOR(__entry->dev),
 			(unsigned long long)__entry->fileid,
 			__entry->fhandle,
-			__entry->offset, __entry->status,
+			(long long)__entry->offset, __entry->arg_count,
+			__entry->res_count, __entry->status,
 			__entry->eof ? " eof" : ""
 		)
 );
diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index cfe0b586eadd4..12deb3bdb2a0f 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -214,7 +214,7 @@ static void nfs_initiate_read(struct nfs_pgio_header *hdr,
 
 	task_setup_data->flags |= swap_flags;
 	rpc_ops->read_setup(hdr, msg);
-	trace_nfs_initiate_read(inode, hdr->io_start, hdr->good_bytes);
+	trace_nfs_initiate_read(hdr);
 }
 
 static void
@@ -247,8 +247,7 @@ static int nfs_readpage_done(struct rpc_task *task,
 		return status;
 
 	nfs_add_stats(inode, NFSIOS_SERVERREADBYTES, hdr->res.count);
-	trace_nfs_readpage_done(inode, task->tk_status,
-				hdr->args.offset, hdr->res.eof);
+	trace_nfs_readpage_done(task, hdr);
 
 	if (task->tk_status == -ESTALE) {
 		set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
-- 
2.39.5